Apple OS X Keyboards

Typing Diacritics And Special Characters:

Adding Special Characters on a Macintosh
Fonts often contain many characters that don’t appear on the Apple keyboard. These characters include accented characters, math symbols, and special punctuation symbols. One simple way to access these characters is to press and hold the base character key for a second or so and you will see a popup menu with the extended character options. For instance, pressing and holding the “a” key will give you these options:
This works for all extended characters based on A, C, E, I, L, N, O, S, U, Y, and Z.Another method is through key stroke commands. Use the following methods to insert special characters in standard desktop applications.

To insert special characters with the Mac keyboard
(Times New Roman font):